Hi SS1199,
I recommend you to check the display status on the External monitor.
There is no way to eliminate it. The only option is to get the screen replaced. Please click on the link below to check the warranty of the system. In case the system is under warranty, send me a private message with the system service tag to assist you further. Please click on my name and click Start Conversation to send me a private message.
Please contact the Out of warranty department If the system is not under warranty, the number is 800-288-4410 if you are in US region, for UK region the number is 844-338-1000, for India the number is 1-800-425-8045 for India and for Canada the number is 1-800-847-4096 . If you belong to a different region, let me know the region you belong to give you the contact information.